In a shared network two or more operators share a Radio Access Network, RAN, in one or more areas. However, the different operators may wish to differentiate their services from the RAN to their respective customers. If not all operators in the shared network want to invest in new Universal Mobile Telecommunication System, UMTS, Terrestrial Radio Access Network, UTRAN, technology as for example High Speed Downlink Packet Access, HSDPA, High Speed Uplink Packet Access, HSUPA, (even called Enhanced Dedicated Channel, E-DCH), Multimedia Broadcast Multicast Service, MEMS, or Voice over IP, VoIP, bearers, it should be possible to block customers of the operators not investing in the new technology. Moreover, in a rural area one operator might want interactive service with bit rates up to 384 kbps, whereas other operators might be content with 128 kbps.
EP 1 443 790 describes a method and a system for sharing the capacity in a radio access multi operator mobile network. It is based on the pre-release 6 roaming based network sharing solution. For the sharing decision the operator, that serves the subscriber demanding the resource, is identified. The available resources for the serving operator are checked, and the use of the available resources in the network, based on a set of sharing rules, is controlled. The means of sharing rules are to prioritize home subscribers over roaming subscribers (e.g. customers of virtual network operators or operators using national roaming), or to control the resource allocation (power) to guarantee each operator an agreed capacity share.
In WO 2004/030393 a resource management for a cellular communication system is described. A resource controller is operable to allocate a radio resource to a subscriber unit in response to an operator identity associated with a service of the subscribers unit, such that different quality of service is achieved for different operators. The cellular communication system has a common radio access network resource divided into a first partition for a first operator and a second partition for a second operator, and the resource controller is operable to allocate resources from the first partition if the operator identity corresponds to the first operator and from the second partition if the operator identity corresponds to the second operator.
In US 2004/00157600 a technique is described for determining whether to grant access for a user equipment to a radio access network in a present position of the user equipment within a communications system. The communications system comprises a control node handling services for the user equipment and an access node controlling the access network.
US 2002/01223348 discloses a technique for precluding or rejecting accesses, in competition areas, to cells of a first operator's network attempted by or on behalf of a mobile terminal which subscribes to a second operators network. Any cell of the first operator network for which the second operator network has a competing cell is designated as a restricted cell, and attempted utilization of the restricted cell by the user equipment unit which subscribes to the second operator network is rejected.
Today's technology thus allows for admission control of different services to ensure a certain level of Quality of Service, QoS. An enhanced Network Sharing, NS, support is presently being standardized in 3rd Generation Partnership Project in 3GPP, for Release 6. Each operator will be able to have its PLMN identity broadcast in the shared network and each operator has a core network. The core network nodes MSC and SGSN can be shared as well. Virtual network operators are not included in our usage the term “operator” here. The 3GPP standard allows differentiation of the services to different customers, but this is managed and controlled by the Core Network, CN. The aim of this service differentiation is to set different QoS on the same service to different customers. Letting CN manage the above proposed service admission control is not a good way forward for two reasons, first, CN is not involved in some of the signaling procedures in question, second it does not prevent abuse from an operator.
When this NS approach is available there will exist UE:s that support this enhanced network sharing feature (from Rel-6) and old UE:s that do not support this enhanced network sharing feature. The network will however be able to handle both UE types. The routing of the traffic to the CN:s of the different operators in the shared network might be performed by somewhat different methods for old and new UE:s.
When old UE:s request a service the Radio Network Controller, RNC, will read the Network Resource Identifier, NRI, in the “Initial Direct Transfer” message. The idea is that the most significant bits in the NRI could specify a customer's operator. The RNC uses this information to route the traffic to the correct Core Network, C-N, i.e. the CN belonging to the operator for the specific user.
The new UE:s that support the enhanced network sharing feature will also send an NRI. However, the 3GPP standardization does not require that the NRI:s will be used for routing the traffic to the correct CN. The new UE will, however, send information of selected Public Land Mobile Network, PLMN, (selected CN), which could then be used for routing.
The purpose of the present invention is to propose a technique for differentiating allowed service access between operators in a shared network of the above indicated kind.